This invention relates to novel L-ascorbic acid and D-erythorbic acid derivatives useful in the preparation of 6-deoxy-6-substituted-L-ascorbic and -D-erythorbic acids and salts thereof. The 6-deoxy-6-substituted compounds are useful as antioxidants.
While L-ascorbic acid and D-erythorbic acids are useful as antioxidants they are relatively labile in aqueous solution, especially under acid conditions. In efforts to provide antioxidants of improved stability, 6-deoxy-6-halo-L-ascorbic acid and 6-deoxy-6-halo-d-erythorbic acid have been prepared, see U.S. Pat. No. 4,043,937 and Carbohydrate Research 68, 313 (1979). 6-Deoxy-L-ascorbic acid has also been prepared, see H. Muller and T. Reichstein, Helv. Chim. Acta 21, 273 (1938).